#pragma once

#include "index0.hpp"
#include "util0.hpp"
// #include "log.hpp"
#include <algorithm>
#include <unordered_map>
#include <jsoncpp/json/json.h>

namespace ns_searcher
{
    struct InvertedElemPrint
    {
        uint64_t doc_id;
        int weight;
        std::vector<std::string> words;
        InvertedElemPrint() : doc_id(0), weight(0) {}
    };

    class Searcher
    {
    private:
        ns_index::Index *index;

    public:
        Searcher() {}
        ~Searcher() {}

    public:
        void InitSearcher(std::string &input)
        {
            index = ns_index::Index::GetInstance();
            std::cout << "获取index单例成功..." << std::endl;
            index->BuildIndex(input);
            std::cout << "建立正排和倒排索引成功..." << std::endl;
        }

        void Search(const std::string &query, std::string *json_string)
        {
            std::vector<std::string> words;
            ns_util::JiebaUtil::CutString(query, &words);
            std::vector<InvertedElemPrint> inverted_list_all;

            std::unordered_map<uint64_t, InvertedElemPrint> tokens_map;
            for (std::string word : words)
            {
                boost::to_lower(word);
                ns_index::InvertedList *inverted_list = index->GetInvertedIndex(word);
                if (nullptr == inverted_list)
                {
                    continue;
                }
                for (const auto &elem : *inverted_list)
                {
                    auto &item = tokens_map[elem.doc_id];
                    item.doc_id = elem.doc_id;
                    item.weight += elem.weight;
                    item.words.push_back(elem.word);
                }
            }
            for (const auto &elem : tokens_map)
            {
                inverted_list_all.push_back(std::move(elem.second));
            }
            std::sort(inverted_list_all.begin(), inverted_list_all.end(), [](const InvertedElemPrint &e1, const InvertedElemPrint &e2)
                      { return e1.weight > e2.weight; });

            Json::Value root;
            for (auto &item : inverted_list_all)
            {
                ns_index::DocInfo *doc = index->GetForwardIndex(item.doc_id);
                if (nullptr == doc)
                {
                    continue;
                }
                Json::Value elem;
                elem["title"] = doc->title;
                elem["desc"] = GetDesc(doc->content, item.words[0]);
                elem["url"] = doc->url;
                elem["id"] = (int)item.doc_id;
                elem["weight"] = item.weight;

                root.append(elem);
            }
            Json::FastWriter writer;
            *json_string = writer.write(root);
        }

        std::string GetDesc(const std::string html_content, const std::string &word)
        {
            const int prev_step = 50;
            const int next_step = 100;
            auto iter = std::search(html_content.begin(), html_content.end(), word.begin(), word.end(), [](int x, int y)
                                    { return (std::tolower(x) == std::tolower(y)); });
            if (iter == html_content.end())
            {
                return "None1";
            }
            int pos = std::distance(html_content.begin(), iter);

            int start = 0;
            int end = html_content.size() - 1;
            if (pos > start + prev_step)
                start = pos - prev_step;
            if (pos < end - next_step)
                end = pos + next_step;
            if (start >= end)
                return "None2";
            std::string desc = html_content.substr(start, end - start);
            desc += "...";
            return desc;
        }
    };
}